BMI and Physical Activity From Childhood Through Adolescence
BMI and Physical Activity From Childhood Through Adolescence
Background Obesity, sedentary lifestyle and poor cardiorespiratory fitness in childhood may increase the risk of health problems later in life.
Purpose The authors studied the association of early childhood weight status with cardiorespiratory fitness and leisure-time physical activity (LTPA) in adolescence. The stability and associations of LTPA and fitness from childhood through adolescence were also studied.
Methods Body mass index (BMI) was assessed annually since birth in a prospective, longitudinal study. The mean BMI between ages 2 and 7 years indicated weight status at preschool age. Fitness was studied with a shuttle run test at age 9 and with a maximal cycle ergometer test at age 17. The same questionnaire was used to assess LTPA at age 9, 13 and 17. Complete data on preschool BMI, LTPA at ages 13 and 17 and fitness at age 17 years was provided by 351 children, while fitness and LTPA data were available for 74 children at ages 9 and 17.
Results Preschool BMI was inversely associated with fitness in adolescence independently of adolescent LTPA (p=0.0001). Children who had a high preschool BMI but whose weight status was reduced in adolescence had similar fitness in adolescence as the children with a persistently low BMI. Regardless of the fitness level in childhood, the children whose LTPA increased between age 9 and 17 had a similar adolescent fitness level as persistently active subjects.
Conclusions It is important to maintain a healthy body weight and a physically active lifestyle from very childhood through adolescence to improve fitness during adolescence.
The soaring prevalence of childhood overweight and obesity that has occurred during the past decades gives cause for great concern. Among the detrimental consequences of childhood overweight on current and future health, children and adolescents with overweight are less fit than their leaner peers. Also, overweight may lead to inactivity and not be the result of it. Whether weight in early childhood is associated with cardiorespiratory fitness (referred later as fitness) or engagement in physical activity in adolescence is, however, not known.
Lack of physical activity is globally the fourth most important risk factor associated with mortality. From very early childhood, a sedentary lifestyle and poor fitness carry many unfavourable health effects. Fitness tracks moderately well from childhood to adolescence, while physical activity shows somewhat weaker stability. Fitness is strongly determined by heredity; approximately half of the interindividual variance of fitness may be explained by genetic factors. Fitness can be improved by increasing physical activity, but the magnitude of improvement varies markedly. In children and adolescents, the association between physical activity and fitness is rather weak or lacking. There are only a few longitudinal studies on fitness and physical activity among children and adolescents, and there is very little data on the effect of changes in physical activity during childhood and adolescence on subsequent fitness.
The main aim of this study was to examine how early childhood weight status is related to fitness and physical activity later in life. We studied the association of preschool body mass index (BMI) and the change in weight status from early childhood to adolescence with fitness and leisure-time physical activity (LTPA) in adolescence. We also studied the stability of LTPA and fitness and their associations through childhood to adolescence. We specifically asked, whether LTPA predicts fitness at age 17 independently of childhood fitness.
Abstract and Introduction
Abstract
Background Obesity, sedentary lifestyle and poor cardiorespiratory fitness in childhood may increase the risk of health problems later in life.
Purpose The authors studied the association of early childhood weight status with cardiorespiratory fitness and leisure-time physical activity (LTPA) in adolescence. The stability and associations of LTPA and fitness from childhood through adolescence were also studied.
Methods Body mass index (BMI) was assessed annually since birth in a prospective, longitudinal study. The mean BMI between ages 2 and 7 years indicated weight status at preschool age. Fitness was studied with a shuttle run test at age 9 and with a maximal cycle ergometer test at age 17. The same questionnaire was used to assess LTPA at age 9, 13 and 17. Complete data on preschool BMI, LTPA at ages 13 and 17 and fitness at age 17 years was provided by 351 children, while fitness and LTPA data were available for 74 children at ages 9 and 17.
Results Preschool BMI was inversely associated with fitness in adolescence independently of adolescent LTPA (p=0.0001). Children who had a high preschool BMI but whose weight status was reduced in adolescence had similar fitness in adolescence as the children with a persistently low BMI. Regardless of the fitness level in childhood, the children whose LTPA increased between age 9 and 17 had a similar adolescent fitness level as persistently active subjects.
Conclusions It is important to maintain a healthy body weight and a physically active lifestyle from very childhood through adolescence to improve fitness during adolescence.
Introduction
The soaring prevalence of childhood overweight and obesity that has occurred during the past decades gives cause for great concern. Among the detrimental consequences of childhood overweight on current and future health, children and adolescents with overweight are less fit than their leaner peers. Also, overweight may lead to inactivity and not be the result of it. Whether weight in early childhood is associated with cardiorespiratory fitness (referred later as fitness) or engagement in physical activity in adolescence is, however, not known.
Lack of physical activity is globally the fourth most important risk factor associated with mortality. From very early childhood, a sedentary lifestyle and poor fitness carry many unfavourable health effects. Fitness tracks moderately well from childhood to adolescence, while physical activity shows somewhat weaker stability. Fitness is strongly determined by heredity; approximately half of the interindividual variance of fitness may be explained by genetic factors. Fitness can be improved by increasing physical activity, but the magnitude of improvement varies markedly. In children and adolescents, the association between physical activity and fitness is rather weak or lacking. There are only a few longitudinal studies on fitness and physical activity among children and adolescents, and there is very little data on the effect of changes in physical activity during childhood and adolescence on subsequent fitness.
The main aim of this study was to examine how early childhood weight status is related to fitness and physical activity later in life. We studied the association of preschool body mass index (BMI) and the change in weight status from early childhood to adolescence with fitness and leisure-time physical activity (LTPA) in adolescence. We also studied the stability of LTPA and fitness and their associations through childhood to adolescence. We specifically asked, whether LTPA predicts fitness at age 17 independently of childhood fitness.
